PHP实现全角字符转为半角方法汇总

<?php  
$str = "０１２３ａｂｃｄｆｗｓ＼＂，．？＜＞｛｝［］＊＆＾％＃＠！～（）＋－｜：；";  
echo "$str";  
echo "<br />";  
$str = preg_replace('/\xa3([\xa1-\xfe])/e', 'chr(ord(\1)-0x80)', $str);  
echo $str;

$queue = array('０' => '0', '１' => '1', '２' => '2', '３' => '3', '４' => '4', '５' => '5', '６' => '6', '７' => '7', '８' => '8', '９' => '9', 
'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd', 'ｅ' => 'e', 'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i', 'ｊ' => 'j', 
'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n', 'ｏ' => 'o', 'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's', 'ｔ' => 't', 
'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x', 'ｙ' => 'y', 'ｚ' => 'z', 'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd', 
'ｅ' => 'e', 'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i', 'ｊ' => 'j', 'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n', 
'ｏ' => 'o', 'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's', 'ｔ' => 't', 'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x', 
'ｙ' => 'y', 'ｚ' => 'z');
echo preg_replace_callback("/([\xef][\xbc][\x90-\x99]|[\xef][\xbd][\x81-\x9a\xa1-\xba])/", 'next_fchar', '０');
function next_fchar($matches){
 global $queue;
 return $queue[$matches[1]];
}

/**
* 字符串半角和全角间相互转换
* @param string $str 待转换的字符串
* @param int  $type todbc:转换为半角；tosbc，转换为全角
* @return string 返回转换后的字符串
*/
function convertstrtype($str, $type) {

    $dbc = array( 
      '０' , '１' , '２' , '３' , '４' , 
      '５' , '６' , '７' , '８' , '９' , 
      'ａ' , 'ｂ' , 'ｃ' , 'ｄ' , 'ｅ' , 
      'ｆ' , 'ｇ' , 'ｈ' , 'ｉ' , 'ｊ' , 
      'ｋ' , 'ｌ' , 'ｍ' , 'ｎ' , 'ｏ' , 
      'ｐ' , 'ｑ' , 'ｒ' , 'ｓ' , 'ｔ' , 
      'ｕ' , 'ｖ' , 'ｗ' , 'ｘ' , 'ｙ' , 
      'ｚ' , 'ａ' , 'ｂ' , 'ｃ' , 'ｄ' , 
      'ｅ' , 'ｆ' , 'ｇ' , 'ｈ' , 'ｉ' , 
      'ｊ' , 'ｋ' , 'ｌ' , 'ｍ' , 'ｎ' , 
      'ｏ' , 'ｐ' , 'ｑ' , 'ｒ' , 'ｓ' , 
      'ｔ' , 'ｕ' , 'ｖ' , 'ｗ' , 'ｘ' , 
      'ｙ' , 'ｚ' , '－' , '　' , '：' ,
      '．' , '，' , '／' , '％' , '＃' ,
      '！' , '＠' , '＆' , '（' , '）' ,
      '＜' , '＞' , '＂' , '＇' , '？' ,
      '［' , '］' , '｛' , '｝' , '＼' ,
      '｜' , '＋' , '＝' , '＿' , '＾' ,
      '￥' , '￣' , '｀'

);

    $sbc = array( //半角
      '0', '1', '2', '3', '4', 
      '5', '6', '7', '8', '9', 
      'a', 'b', 'c', 'd', 'e', 
      'f', 'g', 'h', 'i', 'j', 
      'k', 'l', 'm', 'n', 'o', 
      'p', 'q', 'r', 's', 't', 
      'u', 'v', 'w', 'x', 'y', 
      'z', 'a', 'b', 'c', 'd', 
      'e', 'f', 'g', 'h', 'i', 
      'j', 'k', 'l', 'm', 'n', 
      'o', 'p', 'q', 'r', 's', 
      't', 'u', 'v', 'w', 'x', 
      'y', 'z', '-', ' ', ':',
      '.', ',', '/', '%', ' #',
      '!', '@', '&', '(', ')',
      '<', '>', '"', '\'','?',
      '[', ']', '{', '}', '\\',
      '|', '+', '=', '_', '^',
      '￥','~', '`'

);
if($type == 'todbc'){
return str_replace( $sbc, $dbc, $str ); //半角到全角
}elseif($type == 'tosbc'){
return str_replace( $dbc, $sbc, $str ); //全角到半角
}else{
return $str;
}
}

/**
* 将一个字串中含有全角的数字字符、字母、空格或'%+-()'字符转换为相应半角字符
*
* @access public
* @param string $str 待转换字串
*
* @return string $str 处理后字串
*/
function make_semiangle($str)
{
$arr = array('０' => '0', '１' => '1', '２' => '2', '３' => '3', '４' => '4',
'５' => '5', '６' => '6', '７' => '7', '８' => '8', '９' => '9',
'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd', 'ｅ' => 'e',
'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i', 'ｊ' => 'j',
'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n', 'ｏ' => 'o',
'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's', 'ｔ' => 't',
'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x', 'ｙ' => 'y',
'ｚ' => 'z', 'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd',
'ｅ' => 'e', 'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i',
'ｊ' => 'j', 'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n',
'ｏ' => 'o', 'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's',
'ｔ' => 't', 'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x',
'ｙ' => 'y', 'ｚ' => 'z',
'（' => '(', '）' => ')', '〔' => '[', '〕' => ']', '【' => '[',
'】' => ']', '〖' => '[', '〗' => ']', '“' => '[', '”' => ']',
'‘' => '[', ''' => ']', '｛' => '{', '｝' => '}', '《' => '<',
'》' => '>',
'％' => '%', '＋' => '+', '—' => '-', '－' => '-', '～' => '-',
'：' => ':', '。' => '.', '、' => ',', '，' => '.', '、' => '.',
'；' => ',', '？' => '?', '！' => '!', '…' => '-', '‖' => '|',
'”' => '"', ''' => '`', '‘' => '`', '｜' => '|', '〃' => '"',
'　' => ' ');
return strtr($str, $arr);
}